1. Field of the Invention
This invention relates to a printer for a computer and, more specifically, to a printer which employs a printing element which is movable by means of an electric motor. The apparatus of the present invention includes a coder which monitors the rotation of the motor and provides feedback signals to a microprocessor controlled regulator. Output control lines, from the regulator, are connected to an amplifier which, in turn, supplies power to the motor which is regulated by the regulator. The apparatus of the present invention provides precise control of the motor and associated printing element.
2. Description of the Prior Art
The prior art includes a regulation apparatus for the precise regulation of the speed of rotation of a motor, such as that used in of a dot-matrix printer motor. An actual value counter, which has been programmed with a setpoint, counts pulses and, upon reaching the setpoint count, causes a first auxiliary signal to be generated as a function of the pulse edges of the beginning of a period duration. The basis used here is only a regulation algorithm.
In another process of the prior art, the object is high sensitivity with minimum error, a fast reaction time and a rapid adjustment time with a minimum of fluctuations. This process uses a hardware-based digital control solution.
In another process of the prior art which is employed to regulate the speed of separately excited motors, the motor armature is fed current pulses and, during the pulse interval, the rheostatic armature voltage is measured, compared to a setpoint and the result of the comparison is used to trigger another subsequent direct current pulse. This regulation system is exclusively hardware-based and, in particular, an analog-digital system.
All of these proposals of the prior art, without exception, are based on a hardware-oriented regulation of motor voltage. These are inflexible systems which allow only a regulation algorithm. At the same time, the solutions of the prior art require a high expenditure for hardware components.